---
layout: "default"
title: "_CVarArgPassedAsDouble"
description: "Swift documentation for '_CVarArgPassedAsDouble': Floating point types need to be passed differently on x86_64."
keywords: "_CVarArgPassedAsDouble,protocol,swift,documentation,encode"
root: "/v1.2"
---

<div class="intro-declaration"><code class="language-swift">protocol _CVarArgPassedAsDouble</code></div>

<div class="discussion comment">
    <p>Floating point types need to be passed differently on x86_64
systems.  CoreGraphics uses this to make CGFloat work properly.</p>
</div>

<table class="standard">
<tr>
<th id="inheritance">Inheritance</th>
<td>
<code class="inherits">CVarArgType</code>
<span class="viz"><a href="hierarchy/">View Protocol Hierarchy &rarr;</a></span>
</td>
</tr>



<tr>
<th>Import</th>
<td><code class="language-swift">import Swift</code></td>
</tr>

</table>







<h3>Instance Methods</h3>
<div class="declaration inherited" id="func-encode">
<a class="toggle-link" data-toggle="collapse" href="#comment-func-encode">func encode()</a>
     <span class="required">Required</span>    
<div class="comment collapse" id="comment-func-encode"><div class="p">
    <p>Transform <code>self</code> into a series of machine words that can be
appropriately interpreted by C varargs</p>

    <h4>Declaration</h4>    
    <code class="language-swift">func encode() -&gt; [Word]</code>
    
        <h4>Declared In</h4>
        <a href="../../protocol/CVarArgType/"><code>CVarArgType</code></a>    
</div></div>
</div>


